Design and Numerical Analysis of a Laboratory Scale Lantern for Biofuel Combustion and Flame Structure Analysis
Optimizing Spindle Bearing Performance in Horizontal Milling Machine: A Design of a Monitoring and Control System for Enhanced Longevity
Aligning Machine Shop Engineering Education with Industry Needs: A Case Study of Zimbabwe Tertiary Institutions
Experimental Investigation and Optimization of Turning Process Performance Characteristics using Taguchi Method
Experimental Analysis on Flow Characteristics of Forward-Facing Step
Advancing Conventional Subtractive Manufacturing for Biomedical Implants: A Critical Review of Precision, Surface Integrity, and Functionalization Strategies
Design of Oil-Ammonia Separator for Refrigeration Systems
A Review on Mechanical and Tribological Characteristics of Hybrid Composites
Progressive Development of Various Production and Refining Process of Biodiesel
Design and Experimental Investigation of a Natural Draft Improved Biomass Cookstove
Optimization of Wire-ED Turning Process Parameters by Taguchi-Grey Relational Analysis
Evaluation Of Mechanical Behavior Of Al-Alloy/SiC Metal Matrix Composites With Respect To Their Constituents Using Taguchi Techniques
Multistage Extractive Desulfurization of Liquid Fuel by Ionic Liquids
Isomorphism Identification of Compound Kinematic Chain and Their Mechanism
Development of Electroplating Setup for Plating Abs Plastics
A Comprehensive Review of Biodiesel Application in IDI Engines with Property Improving Additives
A laboratory scale biofuel lantern with a 1960 cm³ reservoir capacity was designed, constructed, and experimentally evaluated for use in combustion education and research. The system features an atmospheric premixed burner that produces a stable, conical blue flame, indicating near complete combustion. A PIC16F877A microcontroller was integrated for real-time monitoring of flame temperature (0–150°C) and fuel status, enhancing its utility as a teaching and diagnostic tool in heat transfer and combustion laboratories. Performance evaluation was conducted using kerosene and a single biodiesel over an extended 60 minute combustion period, with data recorded at one minute intervals to improve statistical robustness. Results showed a consistent decline in reservoir pressure, fuel flow rate, and flame temperature over time. Strong linear relationships were observed between key combustion parameters, with R² values exceeding 0.99 for most correlations. A multiple regression model was developed to predict flame temperature from pressure and fuel flow rate, achieving an R² of 0.994 and a correlation coefficient of 0.997. Residual analysis confirmed the validity of the linear assumptions, with no systematic bias detected. While the lantern was designed for testing various biofuels (e.g., jatropha, palm, peanut), only one biodiesel was tested in this study. Emissions such as CO, NOₓ, and soot were not measured, and comparisons with commercial lanterns were not performed. Therefore, the results support the lantern's functionality as a low cost, reliable educational tool for flame structure analysis and combustion dynamics, particularly in resource constrained institutions. Future scope includes emission profiling, testing with multiple biofuels, and longer-duration experiments to further validate the system.
Bearings are critical components in horizontal milling machines, directly influencing machine performance, precision, and longevity. Premature bearing failure leads to downtime, increased maintenance costs, and reduced productivity. This paper presents a design for a bearing monitoring and control system for horizontal milling machine spindles to enhance bearing longevity, specifically within the context of the Harare Institute of Technology workshop. The design considers key factors affecting bearing life, including temperature, load, and vibration. The system is designed to provide real-time data and control mechanisms for these parameters. The anticipated outcome is a reduction in downtime and maintenance costs, alongside an extension of bearing lifespan.
The study investigated the relationship between training duration, training equipment and facilities and the acquisition of employable skills. The study aimed to show how poor equipment and facilities affect the teaching and learning of machine shop engineering for direct intake students. Surveys and interviews were carried out among twenty recent graduate students, fifteen instructors/lecturers and fifteen industry experts. Analysis of the quantitative and qualitative data revealed that inadequacy of equipment has a great impact on the development of employable skills in machine shop engineering training. Inadequate equipment, facilities, consumables and non-functionality of the current equipment were noted as the main barriers to skills training and development. The findings emphasised the importance of upgrading existing equipment to modern ones and the need to have a systematic maintenance strategy for all the institutions to reduce equipment breakdowns. The study advised policymakers and heads of institutions to increase the duration of industrial training and provide enough funds to buy modern equipment and facilities so that the training stays up to date and meets the needs of the students involved.
The turning process performance is greatly influenced by turning process variables. The Taguchi methodology was used in this work to maximize the performance of the turning process when AISI 304 material was being machined using a conventional cooling method. Parameters of the turning process, including feed rate, cutting speed, and depth of cut, were considered for the work. Utilizing an L9 orthogonal array (OA), the experiments were carried out. Tool wear, surface roughness, and cutting temperature were taken into account as output responses. The findings demonstrated that the Taguchi technique significantly improved the turning performance by determining the ideal process parameters. In order to decrease material waste and boost productivity while machining AISI 304 material, metal cutting enterprises are encouraged to implement these ideal cutting settings.
Fluid flow over the forward-facing step causes the separation, recirculation, and reattachment phenomena. Experiments are conducted on the forward-facing step of variable step inclinations of 30°, 60° and 90° with the fluid flow velocity of 30 m/s. Step heights of 20 mm and 40 mm and a length ratio of 2 are considered for the model preparation. The experimental results observed that the decline in step inclination produces streamline flow on the surface and affects the strength of the recirculation zones. The increase of step height and lower step inclination affect the flow characteristics, considered as favourable insights for prediction of flow behaviour. The observed results have become beneficial in the design of aircraft surfaces, open channels, microfluidic devices and microchannel cooling.
Conventional Subtractive Manufacturing (CSM) remains a cornerstone in the production of biomedical implants, enabling the fabrication of precision-engineered components with complex geometries and stringent dimensional tolerances. Despite the rapid evolution of additive manufacturing, CSM techniques such as CNC machining, milling, turning, and grinding continue to offer superior mechanical integrity and surface finishes required for critical orthopaedic, dental, and spinal implants. This review paper aims to consolidate the contributions of various researchers in advancing CSM for biomedical applications, emphasising precision manufacturing, surface integrity, and post- processing functionalisation strategies. The paper critically examines the effects of cutting parameters, tool geometries, and coolant strategies on microstructural evolution, residual stress development, and surface topography of biomedical alloys such as titanium, cobalt-chromium, and magnesium. It further discusses post-machining surface modification techniques, including polishing, laser texturing, and coating, to enhance biocompatibility and osseointegration. Additionally, the review highlights emerging trends in sustainable machining, digital twin integration, and hybrid subtractive–additive approaches for implant manufacturing. By presenting these insights, this paper serves as a comprehensive reference for researchers and industry professionals, guiding future innovations while addressing current challenges in advancing CSM for biomedical implant development.
